Notice the sudden change in april from ~10% to 14%
Q&A for professional and enthusiast programmers
declare @st_date date = '2013-01-01' select dateadd(week, datediff(week, 0, p.CreationDate), 0) wk, cast(sum( case when votetypeid = 3 then 1 else 0 end ) as float)/ sum( case when votetypeid = 2 then 1 else 0 end ) neg_to_pos_ratio from ( select votes.votetypeid, votes.CreationDate from votes join posts on posts.id = votes.postid where votes.CreationDate > dateadd(year, 0, @st_date) and posts.posttypeid = 1 -- question ) p group by dateadd(week, datediff(week, 0, p.CreationDate), 0) order by dateadd(week, datediff(week, 0, p.CreationDate), 0)